/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.hadoop.hbase.master.procedure;

import java.io.IOException;
import java.util.Arrays;
import java.util.concurrent.CountDownLatch;

import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.RegionInfoBuilder;
import org.apache.hadoop.hbase.master.assignment.TransitRegionStateProcedure;
import org.apache.hadoop.hbase.procedure2.ProcedureStateSerializer;
import org.apache.hadoop.hbase.procedure2.ProcedureSuspendedException;
import org.apache.hadoop.hbase.procedure2.ProcedureYieldException;
import org.apache.yetus.audience.InterfaceAudience;

import org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.InitMetaState;
import org.apache.hadoop.hbase.shaded.protobuf.generated.MasterProcedureProtos.InitMetaStateData;

/**
 * This procedure is used to initialize meta table for a new hbase deploy. It will just schedule an
 * {@link TransitRegionStateProcedure} to assign meta.
 */
@InterfaceAudience.Private
public class InitMetaProcedure extends AbstractStateMachineTableProcedure<InitMetaState> {

    private CountDownLatch latch = new CountDownLatch(1);

    @Override
    public TableName getTableName() {
        return TableName.META_TABLE_NAME;
    }

    @Override
    public TableOperationType getTableOperationType() {
        return TableOperationType.CREATE;
    }

    @Override
    protected Flow executeFromState(MasterProcedureEnv env,
            InitMetaState state) throws ProcedureSuspendedException, ProcedureYieldException, InterruptedException {
        switch(state) {
            case INIT_META_ASSIGN_META:
                addChildProcedure(env.getAssignmentManager().createAssignProcedures(Arrays.asList(RegionInfoBuilder.FIRST_META_REGIONINFO)));
                return Flow.NO_MORE_STATE;
            default:
                throw new UnsupportedOperationException("unhandled state=" + state);
        }
    }

    @Override
    protected boolean waitInitialized(MasterProcedureEnv env) {
        // we do not need to wait for master initialized, we are part of the initialization.
        return false;
    }

    @Override
    protected void rollbackState(MasterProcedureEnv env, InitMetaState state) throws IOException, InterruptedException {
        throw new UnsupportedOperationException();
    }

    @Override
    protected InitMetaState getState(int stateId) {
        return InitMetaState.forNumber(stateId);
    }

    @Override
    protected int getStateId(InitMetaState state) {
        return state.getNumber();
    }

    @Override
    protected InitMetaState getInitialState() {
        return InitMetaState.INIT_META_ASSIGN_META;
    }

    @Override
    protected void serializeStateData(ProcedureStateSerializer serializer) throws IOException {
        super.serializeStateData(serializer);
        serializer.serialize(InitMetaStateData.getDefaultInstance());
    }

    @Override
    protected void deserializeStateData(ProcedureStateSerializer serializer) throws IOException {
        super.deserializeStateData(serializer);
        serializer.deserialize(InitMetaStateData.class);
    }

    @Override
    protected void completionCleanup(MasterProcedureEnv env) {
        latch.countDown();
    }

    public void await() throws InterruptedException {
        latch.await();
    }
}
